diff --git a/tests/regressiontests/cache/tests.py b/tests/regressiontests/cache/tests.py
index 4100a8cb1df..fe365f9097e 100644
--- a/tests/regressiontests/cache/tests.py
+++ b/tests/regressiontests/cache/tests.py
@@ -265,7 +265,7 @@ class FileBasedCacheTests(unittest.TestCase, BaseCacheTests):
     """
     def setUp(self):
         self.dirname = tempfile.mkdtemp()
-        self.cache = get_cache('file:///%s' % self.dirname)
+        self.cache = get_cache('file://%s' % self.dirname)
 
     def tearDown(self):
         shutil.rmtree(self.dirname)